Planar heating element and manufacturing method for same

A planar heating element comprising:

• a sheet-like electrical insulating substrate,
• a sheet-like polymer resistor placed on the electrical insulating substrate,
• at least one pair of electrodes that includes thin metal wires covered with conductive cover layers, that is placed along a sheet-like surface of the polymer resistor, and that supplies electricity to the polymer resistor, and
• sheet-like insulating cover material that is bonded to the electrical insulating substrate through hot melt so as to cover the electrodes and the polymer resistor, the insulating cover material facing to the electrical insulating substrate, the electrodes and the polymer resistor being placed between the insulating cover material and the electrical insulating substrate,
• wherein sectional shape of the cover layers in the electrodes is of an ellipse in general with major axis extending in a direction along a sheet-like surface of the electrical insulating substrate.